In case you didn't know, in politics a "dog whistle" is coded language that has a superficial meaning for everybody, but also a special resonance for certain constituencies. Using dog whistles lets politicians deny they meant to say anything nasty, bigoted or controversial.

Speaking to the National Action Network the day after a testy but racially irrelevant exchange with Republican members of a House panel, Attorney General Eric Holder said, "The last five years have been defined ... by lasting reforms even in the face of unprecedented, unwarranted, ugly and divisive adversity." He continued: "If you don't believe that, you look at the way -- forget about me, forget about me. You look at the way the attorney general of the United States was treated yesterday by a House committee. ... What attorney general has ever had to deal with that kind of treatment? What president has ever had to deal with that kind of treatment?"

Now, bear in mind the audience. The National Action Network is Al Sharpton's plaything, often providing the shock troops Sharpton needs for rent-a-mob protests, shakedown operations and MSNBC photo ops. Holder didn't say criticism of him and Obama is racially motivated, but the notion the audience (or the media) would take it any other way doesn't pass the laugh test.

Holder's hypocrisy is stunning given that he once famously chastised Americans as being "cowards" for not talking openly about race. Who's the coward now?

For the record, there's nothing special about the rough time Holder has received. Forget Harry Daugherty of Teapot Dome fame or John Mitchell, who went to prison. Ed Meese's critics had "Meese Is a Pig" posters printed up. Janet Reno and John Ashcroft never got cake and ice cream from opponents.

The best recent comparison is probably Alberto Gonzales, George W. Bush's second attorney general, because like Holder, he was a fairly incompetent partisan loyalist with a thin skin. Gonzales was treated brutally by Democrats. Some even tried to impeach him. I don't recall Gonzales insinuating that such efforts were anti-Latino.

Holder has deserved all he's gotten. He earned his contempt of Congress citation by refusing to provide documents on the disastrous Fast and Furious operation that left an American dead from a gun the U.S. government put on the street. If anything, Holder deserves more grief, particularly from a media that seem to have forgotten his efforts to surveil journalists' phone records and name Fox News'James Rosen an unindicted co-conspirator in an espionage case.

Even inside the White House, Holder is considered too political. "Holder substitutes his political judgment for his legal judgment, and his political judgment isn't very good," says an unnamed White House official, according to the Washington Post's David Ignatius.

Holder's remarks come at a convenient time. In a widely discussed New York Magazine essay, Jonathan Chait argues that race relations have gotten worse under Obama. Chait believes that liberals have become obsessed with conservative racism as the real explanation for everything Republicans do. Meanwhile, he says conservatives have cocooned themselves in a kind of righteous victimhood, where racism is a relevant issue only when conservatives are falsely accused of it. (It's a fair point that conservatives should be more conspicuously concerned about racism.)

It is an at times brave and insightful, if not uniformly persuasive, essay. The Holder episode casts light on one of his arguments. According to Chait, Obama has steadfastly refused to make race a national issue, even as the ugly racial conversation has raged. "In almost every instance when his blackness has come to the center of public events, however, [Obama] has refused to impute racism to his critics," Chait writes.

That's largely (though not entirely) true about what the president has said himself. But it is manifestly untrue about what he has allowed to be said on his behalf. He didn't mind the racial theater congressional Democrats put on when black congressmen marched through Tea Party protests to sign Obamacare. One of those congressmen, civil rights hero John Lewis, gave a stirring speech at the 2012 Democratic Convention and suggested that a vote for the GOP amounted to "going back" to Jim Crow.

Republican presidents are routinely expected to denounce outrageous comments by members of their own party, never mind members of their Cabinet. Not Obama. His feigned aloofness is his exoneration, even as racial politics get ever more poisonous, thanks in part to his whistling lap dog.